I'd drive 300 miles for another "M"!! Those are the cadillac of Lawnboys. $50 is a steal. Go for it.

Yes the "M" is the only Lawnboy with injection.

I'll bet it smokes alot because the injector valves leak when they sit and it will take a while before all the built up oil burns off.

You will like it.

Neal

Thanks Neal... I read through a few posts you had concerning your 'Smoking' M.

I think I'm going to pull the trigger on this one pending a good introduction (starts right up, no leaks, working SP, etc.)

My policy is take ANY "M" series regardless of condition if the price is right.

I'm a little bit more selective when it comes to other LB's though. The thing with the "M" is they can be parted out and you could return five times your money if you had to.

Some of the older self propel models have a fussy drive system but lets cross that bridge when we get there.

Enjoy it! Post some pics if you can!!

Neal

My new 'M'
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Tied up in the truck for the ride home
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Made it home and into the shed safely
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Another angle in the shed
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My 10323 that I'm currently bringing back to 'solid' working condition (not necessarily a restore, but a general overhaul)and the 10550 is in the box behind the 10323 on the table.

The 10685 - extremely reliable, powerful, and I'm happy to have it.
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Another 10323, this one NIB and never opened... (ignore the pumpkin :) )
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That 'M' will clean up nice. I use a soap called 'Roll-Off' on my mowers, bags and all. Just a hose spray, no pressure washer.

Roll-Off? Is that an auto-store product? Wal-mart/K-Mart?

The "oil injection" is a fancy word.

The oil is actually drawn into the carburetor airstream with a venturi - just like fuel is drawn into the carburetor. Another application of Burnelli's principle. The system works well and you don't have to mix oil with the fuel.

By the way... the two NIB LBs need to be sold to fund a new ZT rider...

Got some more news from the doctor today concerning knee surgery (my 4th and 5th (two procedures)) and really need to focus funds towards a more maneuverable rider.

I wouldn't be able to ship these anytime soon, but if anyone in the Southern Louisiana area is interested, please let me know...

uproar90,
Congratulations on the new M-series. You have the exact model that I have, a 1991 M21BMRC.

You can download free pdfs of the M-series repair manual and owners manual at lawnboy's website.

larryf,
The statements about oil injection above are not true of the M-series. There is in fact an oil pump which is gear driven by the crankshaft.

Any thoughts on where to buy rear wheels for this thing?

Or any parts for that matter? I had read that parts would be hard to come by, but I didn't realize that meant near impossible...

My right-rear wheel is bald which makes for a weird 'pulling' sensation while trying to use the SP.

Made a few passes w/ the 'M' today just to 'get acquainted'.

Then finished the front yard w/ the 10685, rode the LT for the rest of the rear yard and then fired the 'M' again for a few trim spots in the back... It started surging really strange and I just started thinking that something must've gone wrong on my last run... Turns out it was just out of gas :)

Put some fresh gas and a bit of the Mobil 1 2T oil and the smokiness immediately went away and surging disappeared...

The cut quality is superb, and this is only w/ a generic blade. I can see how a gator or some sort of mulching blade would really bring this thing to life.

It was a bit bulkier and seemed heavier than my 10685, but it really does handle like a Cadillac... Big cruiser type of machine...

(just need to fix that bald tire)

You can probably get $750 to $950 for the new 10550 and $350 for the 10323. I recently got $375 for my used (but very nice) 10550. I recommend putting them on ebay.
'Roll-Off' is not usually found in stores - I wish it were. Well, maybe at marine supplies. Here's a link:

Here is a link that might be useful: Roll Off Multi-Purpose Cleaner

"(just need to fix that bald tire)"

I hurriedly scanned the post and assume you are referring to the "M" series? I am not familiar with them but the on the self-propelled wheels for "F", I have drilled out the 3 (?) pins holding the gear to the inside of the wheel, replaced with relatively inexpensive matching wheel from regular push mower by drilling holes in it and reattaching the gear. Others have done this also.

Walt Conner

I hadn't looked for new M-series wheels in a long time, but a price check for a rear wheel (LB PN 684574 which says replaced by 684576) is $66.80 on rcpw.com. (WOW!)

How is the pull-back force on your mower? Meaning, how easily do the rear wheels roll when you pull the mower back? The SP system (specifically the pull-back) is the only area of significant frustration that I have experienced in owning my M-series. If the links below work, it will show the original M-series drive system (like on your mower used on the 1989-1991 models), and the updated drive system used on the later model M-series (like model 10591 from 1993-1996). The 1992 models are kindof a hybrid. The drive system on some models are like the newer style sytem, and some (like the 680523) incorporate the newer engagement system, but don't have the wheel clutch setup.

You'll notice one of the major changes is the engagement lever (part 14 in first figure), which is supported via a bushing that rides on the axle in the original design. This was replaced by an engagement lever system (parts 4-14 in the second figure) which mounts to the transmission housing in the later models.

The second major change is addition of the wheel clutch system that was common with many of the Toro / Lawnboy designs of the 1990s. The later models have plastic rear wheels instead of the metal wheels on the original M. The transmission is identical between the two models with the exception of the axle.

I contacted Lawnboy a few times about the drive system and whether a kit existed to update to the 10591 setup, and was told it did not, but I eventually scrounged around enough on ebay to find a used 10591 style M-series transmission. I also got a complete transmission assembly from a 10515 or 10525 as a parts donor. The donor assembly included the wheels, drive clutch setups and height adjusters. That left me only a few parts to buy new to complete the update of the drive system. I completed the swap on my mower about 4 years ago, and I couldn't be happier with the change.

Original M21BMRC drive system:

Updated style drive system on 10591 model:

Now a pic of my mower after the swap...
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saxman1 - thanks for the info on roll off... I've sent the link onto my BIL who is heavy into boats (aftermarket marine (amarket.com)) to see if he's heard of it, or can possibly get some in...

Walt - I think I know what you're talking about... I'm guessing the gears are held onto the wheels just like those of the 10323 w/ those steel pins? Drill those out, center the gear over a new 'cheapie' wheel, bolt it on, eh?

Anyone know if there was a thread around here describing this and/or showing how its done?

Thanks again!

-mike

uproar,
On the M-series wheels, the drive gear is held on by the two screws visible from the exterior of the wheel. The orginal wheels have a lip near the outer edge of the wheel which rides in a groove on the dustcover. I imagine that you could be creative in choosing a wheel that you could mount the gear to and make it work. One of the challenges would be keeping dirt and grime out of the mechanism without the dust cover fitting properly with the wheel. You might be able to use the newer style dust covers as well if you find a suitable wheel.

You might find the original wheels for sale on ebay. I have seen new wheels sell for alot less there, but they are not very common. Good luck.

I still have my M21BMR purchased new in 1989 by my wife for Fathers day
On my 3rd set of back wheels
Current tread was falling off
Filled tire with construction adhesive last year
Still working fine this year
I do grease all 4 fittings at each mowing
Best WB mower I have ever used

I have two M-Series Both run, back wheels for the one are expensive. The one like in the picture smokes alot on start up but works out of it. Wants to die alot when engaging the blade. Have to play with it to mow. Other one is older one with the two screws on outside of rear wheels, Brake pad was gone so I tied the brake back and put a toggle switch on it for off and on. Starts real easy with the brake lever tied back, other one hard to pull with the brake lever tied back. LB the only way to go. Using Synthetic Amsoil 80-1 on two of my LB and they run fine.